This study examined the effects of high- vs. moderate-intensity interval training on cardiovascular fitness, leptin levels and ratings of perceived exertion (RPE) in obese female adolescents. Forty-seven participants were randomly assigned to one of three groups receiving either a 1:1 ratio of 15 s of effort comprising moderate-intensity interval training (MIIT at 80% maximal aerobic speed: MAS) or high-intensity interval training (HIIT at 100% MAS), with matched 15 s recovery at 50% MAS, thrice weekly, or a no-training control group. The HIIT and MIIT groups showed improved (p < 0.05) body mass (BM), BMI Z-score, and percentage of body fat (%BF). Only the HIIT group showed decreased waist circumference (WC) (p = 0.017). The effect of exercise on maximal oxygen uptake (VO2max) was significant (p = 0.019, ES = 0.48 and p = 0.010, ES = 0.57, HIIT and MIIT, respectively). The decrease of rate-pressure product (RPP) (p < 0.05, ES = 0.53 and ES = 0.46, HIIT and MIIT, respectively) followed the positive changes in resting heart rate and blood pressures. Blood glucose, insulin level and the homeostasis model assessment index for insulin decreased (p < 0.05) in both training groups. Significant decreases occurred in blood leptin (p = 0.021, ES = 0.67 and p = 0.011, ES = 0.73) and in RPE (p = 0.001, ES = 0.76 and p = 0.017, ES = 0.57) in HIIT and MIIT, respectively. In the post-intervention period, blood leptin was strongly associated with %BF (p < 0.001) and VO2max (p < 0.01) in the HIIT and MIIT groups, respectively, while RPE was strongly associated with BM (p < 0.01) in the HIIT group. The results suggest that high-intensity interval training may produce more positive effects on health determinants in comparison with the same training mode at a moderate intensity.

The aim of this study was to compare the effects of 12 weeks of high-intensity interval training (HIIT) with the effects of 12 weeks of plyometric exercise combined with HIIT (P+HIIT) on anthropometric, biochemical, and physical fitness data in young obese females. Sixty-eight participants (age, 16.6 ± 1.3 y; body mass, 82.8 ± 5.0 kg; body fat, 39.4% ± 3.3%; body mass index z score, 2.9 ± 0.4) were assigned to 1 of 3 groups: HIIT (2 blocks per session of 6–8 bouts of 30-s runs at 100% velocity at peak oxygen uptake, with 30-s active recovery between bouts at 50%velocity at peak oxygen uptake (n = 23)); P+HIIT (2 blocks per session of 3 different 15-s plyometric exercises with 15-s passive recoveries, totaling 2 min for each plyometric exercise + the same HIIT program (n = 26)); or control (no exercise (n = 19)). Anthropometric (body mass, body mass index z score, body fat, lean body mass, and waist circumference), biochemical (plasma glucose, insulin, leptin and adiponectin concentrations, leptin/adiponectin ratio, and homeostasis model assessment of insulin resistance (HOMA-IR)), physical fitness (peak oxygen uptake, velocity at peak oxygen uptake, squat jump, and countermovement jump performances), and energy intake data were collected. Both training programs improved the anthropometric, biochemical, and physical fitness variables. However, the P+HIIT program induced greater improvements than did the HIIT program in lean body mass (+3.0% ± 1.7%), plasma glucose and leptin concentrations (–11.0% ± 4.7% and –23.8% ± 5.8%, respectively), plasma leptin/adiponectin ratio (–40.9% ± 10.9%), HOMA-IR (–37.3% ± 6.2%), and squat jump performance (22.2% ± 7.5%). Taken together, these findings suggest that adding plyometric exercises to a HIIT program may be more beneficial than HIIT alone in obese female adolescents.

Exercise has beneficial effects on obesity and diabetes treatments. However, obese subjects do not closely adhere to training programs probably because of the monotony of the continuous exercise that is frequently proposed. To increase adherence to training programs, intermittent exercise, which is less monotonous, may be more appropriate. The purposes of this study were to determine the perceptually less hard exercise (continuous vs intermittent exercise) and to analyze the impact of a training program on the basis of this exercise in obese women with and without type 2 diabetes. Twenty type 2 diabetic obese women and 20 obese women without diabetes were recruited. In each group, 10 patients integrated a training program (i.e., training groups), whereas the remaining patients were untrained (i.e., control groups). The training groups performed a continuous exercise and an intermittent exercise to determine the perceptually less hard exercise thanks to lower ratings of perceived exertion (RPE). Then, a training program that included 32 min (3 d x wk(-1) x 10 wk(-1)) of the perceptually less hard exercise was proposed to training groups. RPE were significantly lower during the intermittent exercise compared to the continuous exercise in the obese women with or without diabetes (RPE = 12.3 +/- 2.3 vs 13.7 +/- 2.3 and RPE = 11.9 +/- 1.1 vs 13.2 +/- 1.6, respectively). After the training program, significant beneficial effects on the glycosylated hemoglobin (6.8 +/- 1.4% vs 6.5 +/- 1.2%), body mass (97.1 +/- 16.9 vs 95.2 +/- 16.2 kg), body mass index (37.6 +/- 6.1 vs 36.8 +/- 6.0 kg x m(-2)), and on the HR and the walked distance limit were noticed in the training groups. The obese women with or without diabetes perceived the intermittent exercise as being less hard than the continuous exercise, and a training program based on intermittent exercises produced beneficial effects on obesity and type 2 diabetes.

The aim of this study was to define the time-motion (i.e., fighting, preparatory and breaking activity), technical (i.e., attack, timed-attack, counterattack, blocking and grasps) and tactical (i.e., upper limb, lower-limb, combination and throwing) profiles of the senior top-level karate competition played under the most recent rules of the International Karate Federation in relation to gender, match outcome and weight categories. Time-motion, tactical actions and technical executions were investigated of senior karatekas (n = 60) during the Karate World Championship. The referee's decisions caused an overall activity-to-break ratio of ~1:1.5 with a significant difference (P = 0.025) between karateka's weight categories (light = 1:1.5; middle = 1:2 and heavy = 1:1). High-intensity actions (i.e., attack and defensive actions performed quickly and powerfully) were higher in male compared to female athletes. Top-level karatekas used upper limb techniques more than lower limb ones, with both applied in the head more than in the body. For the high-intensity-actions to pause ratio and the percentage of combined techniques, light weight category was significantly higher than middle weight category. These findings suggest that training programs may need to be specific to the requirements of the gender and weight categories.

Introduction: Exercise tolerance testing is an integral part of the pulmonary rehabilitation (PR) management of patients with chronic obstructive pulmonary disease (COPD). The 6-minute stepper test (6MST) is a new, well-tolerated, reproducible exercise test, which can be performed without any spatial constraints. Objective: The aim of this study was to compare the results of the 6MST to those obtained during a 6-minute walk test (6MWT) and cardiopulmonary exercise testing (CPET) in a cohort of COPD patients. Methods: Ninety-one COPD patients managed by outpatient PR and assessed by 6MST, 6MWT, and CPET were retrospectively included in this study. Correlations between the number of steps on the 6MST, the distance covered on the 6MWT, oxygen consumption, and power at the ventilatory threshold and at maximum effort during CPET were analyzed before starting PR, and the improvement on the 6MST and 6MWT was compared after PR. Results: The number of steps on the 6MST was significantly correlated with the distance covered on the 6MWT (r=0.56; P<0.0001), the power at maximum effort (r=0.46; P<0.0001), and oxygen consumption at maximum effort (r=0.39; P<0.005). Performances on the 6MST and 6MWT were significantly improved after PR (570 vs 488 steps, P=0.001 and 448 vs 406 m, respectively; P<0.0001). Improvements of the 6MST and 6MWT after PR were significantly correlated (r=0.34; P=0.03). Conclusion: The results of this study show that the 6MST is a valid test to evaluate exercise tolerance in COPD patients. The use of this test in clinical practice appears to be particularly relevant for the assessment of patients managed by home PR.